The invention relates generally to apparatus and methods for isolating and collecting living cells for later use in medical procedures. More particularly, the invention relates to apparatus and related methods in which living cells from a human or animal donor are isolated and collected inside a sealed enclosure. After collection, the isolated cells can be removed from the enclosure for use in medical procedures.
The development of new medical procedures has lead to a need for improved apparatus and methods for isolating and collecting living cells from human and animal donors. In certain types of cell therapy, living cells from a donor are injected into a patient. Those cells lodge inside the patient's body and function to provide a therapeutic benefit to the patient. As an illustrative example, cell therapy is coming into increasing use in the treatment of diseases and injuries to the human liver.
In some cell therapy methods, healthy liver tissue is taken from an animal donor, which is often a pig. The liver tissue is chemically treated to break down, or "digest," the structure of the liver. The digested liver tissue is then filtered to isolate and collect hepatocytes, i.e., living, functional liver cells.
The collected cells are then injected or implanted into a diseased or injured liver or elsewhere inside a human patient. The donated cells lodge inside the patient, where they act to assist and augment the functioning of the recipient's own diseased or injured liver. The functioning of the patient's liver is significantly enhanced by the presence of these donor cells, and the patient enjoys a distinct therapeutic benefit.
The practicability of cell therapy treatment of the liver and related cell therapy techniques is obviously dependent upon the availability of sufficient quantities of healthy liver cells from a donor. Currently, digested liver tissue is most often processed by washing and filtering the digested tissue manually through one or more screens or meshes having openings or pores of appropriate size.
Known techniques for collecting and isolating living cells are less than ideal. Processing the cells by manual washing and filtration is time consuming and labor intensive. The cells can be damaged, killed or otherwise rendered incapable of performing their desired functions due to rough handling. Moreover, known methods are typically performed in "open" procedures in which the tissue and cells are not contained inside any closed container. This may compromise the sterility of the cells collected and isolated using the known methods.
A definite need exists, therefore, for apparatus and methods for isolating and collecting cells in which cell harvesting can be made quicker and less labor intensive, damage to the cells substantially reduced, and sterility of the collected cells made more secure.